6) mcpof x + 42, mcpor - 87°,
and mzfor r + 65. find x.

  x =  -10 .

Explanation:

         x + 42 + x + 65  = 87 ;  Solve for "x" ; 

           2x + 107 = 87 .
 
Subtract "107" from each side of the equation:

           2x + 107 − 107 = 87 − 107 ;

             2x = -20 ;

Divide each side of the equation by "2" ; to isolate "x" on one side of the equation; and to solve for "x" ;

             2x / 2  =  -20/2 ;

                 x = -10 .

We need the pictures of the graphs